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VCAIMAGES

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VCAIMAGES = [real]
Default: VCAIMAGES = -1 

Description: The tag VCAIMAGES allows to perform two different MD's with e.g. different POTCAR files and perform force averaging between the two calculations.


The tag VCAIMAGES gives the weight of the first image. The weight of the second image is 1-VCAIMAGES. Each image needs a seperate directory with all important files in it (POSCAR, INCAR, KPOINTS and POTCAR). The subdirectories for images one and two have to be named 01 and 02, respectively. The tags VCAIMAGES and NCORE_IN_IMAGE1 have to be the same in the INCAR files of the parent directory and both subdirectories. POTCAR, POSCAR and KPOINTS are first seeked in the root directory, and if they do not exist they have to be in the subdirectories 01 or 02. The POSCAR files need to be the same in subdirectories 01 and 02. The KPOINTS files can differ in the subdirectories.

Forces and energies are averaged over the two images.

By setting this tag to VCAIMAGES>-1 (regardless of the value) the tag IMAGES=2 is set. This means the communicator is split into two images. To set the number of cores in the first image the tag NCORE_IN_IMAGE1 has to be set. The second image contains the remaining number of cores.

Related Tags and Sections

NCORE_IN_IMAGE1